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1.
Biofabrication ; 16(3)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38569494

RESUMO

The ever-stricter regulations on animal experiments in the field of cosmetic testing have prompted a surge in skin-related research with a special focus on recapitulation of thein vivoskin structurein vitro. In vitrohuman skin models are seen as an important tool for skin research, which in recent years attracted a lot of attention and effort, with researchers moving from the simplest 2-layered models (dermis with epidermis) to models that incorporate other vital skin structures such as hypodermis, vascular structures, and skin appendages. In this study, we designed a microfluidic device with a reverse flange-shaped anchor that allows culturing of anin vitroskin model in a conventional 6-well plate and assessing its barrier function without transferring the skin model to another device or using additional contraptions. Perfusion of the skin model through vascular-like channels improved the morphogenesis of the epidermis compared with skin models cultured under static conditions. This also allowed us to assess the percutaneous penetration of the tested caffeine permeation and vascular absorption, which is one of the key metrics for systemic drug exposure evaluation.


Assuntos
Epiderme , Pele , Animais , Pele/metabolismo , Epiderme/química , Epiderme/metabolismo , Absorção Cutânea , Cafeína/farmacologia , Cafeína/análise , Cafeína/metabolismo , Perfusão
2.
An Acad Bras Cienc ; 96(1): e20230067, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656055

RESUMO

Platinum nanoparticles supported by carbon nanotubes were obtained by a simple chemical route and used for preparation of electrochemical sensor towards caffeine determination. Carbon nanotubes were used before and after an acid treatment, yielding two different materials. Morphological and structural characterization of these materials showed platinum nanoparticles (size around 12 nm) distributed randomly along carbon nanotubes. Modified electrodes were directly prepared through a dispersion of these materials. Voltammetric studies in the presence of caffeine revealed an electrocatalytic effect of platinum oxides, electrochemically produced from the chemical oxidation of the platinum nanoparticles. This behavior was explored in the development a selective method for caffeine determination based on platinum oxide reduction at a lower potential value (+0.45 V vs. Ag/AgCl). Using the best set of experimental conditions, it was shown a linear relationship for the caffeine concentration ranging from 5.0 to 25 µmol L-1 with a sensitivity of 449 nA L µmol-1. Limits of detection and quantification of 0.54 and 1.80 µmol L-1 were calculated, respectively. Recovery values for real samples of caffeine pharmaceutical formulations between 98.6% and 101.0% (n = 3) were obtained using the proposed procedure. Statistical calculations showed good concordance (95% confidence level) between the added and recovery values.


Assuntos
Cafeína , Técnicas Eletroquímicas , Nanopartículas Metálicas , Nanotubos de Carbono , Platina , Nanotubos de Carbono/química , Cafeína/análise , Cafeína/química , Platina/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Reprodutibilidade dos Testes , Oxirredução
3.
PLoS One ; 19(3): e0298331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38530838

RESUMO

Electrochemical measurements, which exhibit high accuracy and sensitivity under low contamination, controlled electrolyte concentration, and pH conditions, have been used in determining various compounds. The electrochemical quantification capability decreases with an increase in the complexity of the measurement object. Therefore, solvent pretreatment and electrolyte addition are crucial in performing electrochemical measurements of specific compounds directly from beverages owing to the poor measurement quality caused by unspecified noise signals from foreign substances and unstable electrolyte concentrations. To prevent such signal disturbances from affecting quantitative analysis, spectral data of voltage-current values from electrochemical measurements must be used for principal component analysis (PCA). Moreover, this method enables highly accurate quantification even though numerical data alone are challenging to analyze. This study utilized boron-doped diamond (BDD) single-chip electrochemical detection to quantify caffeine content in commercial beverages without dilution. By applying PCA, we integrated electrochemical signals with known caffeine contents and subsequently utilized principal component regression to predict the caffeine content in unknown beverages. Consequently, we addressed existing research problems, such as the high quantification cost and the long measurement time required to obtain results after quantification. The average prediction accuracy was 93.8% compared to the actual content values. Electrochemical measurements are helpful in medical care and indirectly support our lives.


Assuntos
Cafeína , Café , Cafeína/análise , Boro/química , Eletrodos , Aprendizado de Máquina , Eletrólitos
4.
Sensors (Basel) ; 24(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38544236

RESUMO

Caffeine is the most widely consumed stimulant and is the subject of significant ongoing research and discussions due to its impact on human health. The industry's need to comply with country-specific food and beverage regulations underscores the importance of monitoring caffeine levels in commercial products. In this study, we propose an alternative technique for caffeine analysis that relies on mid-infrared laser-based photothermal spectroscopy (PTS). PTS exploits the high-power output of the quantum cascade laser (QCL) sources to enhance the sensitivity of the mid-IR measurement. The laser-induced thermal gradient in the sample scales with the analytes' absorption coefficient and concentration, thus allowing for both qualitative and quantitative assessment. We evaluated the performance of our experimental PTS spectrometer, incorporating a tunable QCL and a Mach-Zehnder interferometer, for detecting caffeine in coffee, black tea, and an energy drink. We calibrated the setup with caffeine standards (0.1-2.5 mg mL-1) and we benchmarked the setup's capabilities against gas chromatography (GC) and Fourier-transform infrared (FTIR) spectroscopy. Quantitative results aligned with GC analysis, and limits of detection matched the research-grade FTIR spectrometer, indicating an excellent performance of our custom-made instrument. This method offers an alternative to established techniques, providing a platform for fast, sensitive, and non-destructive analysis without consumables as well as with high potential for miniaturization.


Assuntos
Bebidas , Cafeína , Humanos , Cafeína/análise , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Bebidas/análise , Lasers Semicondutores
5.
Huan Jing Ke Xue ; 45(3): 1468-1479, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471862

RESUMO

Pharmaceuticals and personal care products (PPCPs) are a group of emerging contaminants causing detrimental effects on aquatic living organisms even at low doses. To investigate the contamination characteristics and ecological risks of PPCPs in drains flowing into the Yellow River of Ningxia, 21 PPCPs were detected and analyzed using solid phase extraction and ultra-high performance liquid chromatography-mass spectrometry in this study. All 21 targeted compounds were detected in the drains, with total concentrations ranging from 47.52 to 1 700.96 ng·L-1. Ciprofloxacin, acetaminophen, benzophenone-3, and diethyltoluamide were the more commonly detected compounds, with detection frequencies exceeding 80%. The five highest-concentration PPCPs were acetaminophen, diethyltoluamide, caffeine, benzophenone-3, and levofloxacin, with the maximum concentrations of 597.21, 563.23, 559.00, 477.28, and 473.07 ng·L-1, respectively. Spatial analysis showed that the pollution levels of PPCPs in the drains of the four cities were different, with average concentrations of ∑PPCPs in the order of Yinchuan>Shizuishan>Wuzhong>Zhongwei. The total concentration of PPCPs before flowing into the Yellow River ranged from 124.82 to 1 046.61 ng·L-1. Source analysis showed that livestock and poultry breeding wastewater was the primary source for sulfadiazine and oxytetracycline, whereas medical wastewater was the primary source for levofloxacin and ciprofloxacin. The primary sources of triclocarban and triclosan were domestic sewage and industrial wastewater, whereas the primary source of caffeine and diethyltoluamide was domestic sewage. The pollution of diciofenac, cimetidine, triclocarban, and triclosan in the drains was positively correlated with the regional population and economic development level. The ecological risk assessment indicated that levofloxacin, diclofenac, gemfibrozil, benzophenone-3, and triclocarban posed high risks to aquatic organisms in drains flowing into the Yellow River. It is worthwhile to consider the mixture risk of the PPCPs that exhibited high risk at most sampling sites.


Assuntos
Benzofenonas , Carbanilidas , Cosméticos , Triclosan , Poluentes Químicos da Água , Acetaminofen , Organismos Aquáticos , Cafeína/análise , Ciprofloxacina , Cosméticos/análise , Monitoramento Ambiental/métodos , Levofloxacino/análise , Preparações Farmacêuticas , Medição de Risco , Rios/química , Esgotos/análise , Águas Residuárias , Poluentes Químicos da Água/análise
6.
J Hum Lact ; 40(2): 307-313, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38407091

RESUMO

BACKGROUND: Human milk banks have been established to provide human milk to preterm infants who are unable to obtain milk from their mothers. Donor screening methods vary, and prospective donors are commonly screened for drug and recreational substance use through behavioral screening. Although the risk of illegal drug consumption in Japan is extremely low, caffeine may be consumed unknowingly and can be found in human milk. To date, only a few reports have been conducted on the concentration of caffeine in donor milk. RESEARCH AIM: This study aimed to examine the pre-pasteurization levels of caffeine in human milk donated to a milk bank in Japan. METHODS: This was a cross-sectional, observational study of caffeine concentrations in human milk donated to a human milk bank in Japan. Caffeine concentration in the donor milk was measured using high-performance liquid chromatography. RESULTS: Caffeine was detected in 70% of the donor milk samples (N = 350). The median (range) of caffeine concentration was 0.46 [< 0.10, 7.54] mg/L, and 64.0% of the samples had less than 1 mg/L of caffeine. The caffeine concentration varied widely among as well as within individuals. CONCLUSION: The average caffeine concentration in Japanese donor milk samples was higher than that previously reported in samples from Spain, but the range was similar. Donors should be informed that caffeine intake should be within a moderate range, to further increase the safety of donor milk.


Assuntos
Bancos de Leite Humano , Leite Humano , Feminino , Lactente , Recém-Nascido , Humanos , Leite Humano/química , Cafeína/análise , Japão , Estudos Transversais , Recém-Nascido Prematuro , Aleitamento Materno
7.
Artigo em Inglês | MEDLINE | ID: mdl-38309045

RESUMO

A UV-HPLC method optimized by Box-Behnken design model was developed to determine caffeine in pharmaceutical preparations and urine samples. The chromatographic conditions followed were mobile phase: methanol/water/ citrate buffer (pH 4.6) (40:25:35, v/v/v),AcclaimTMDionex C18 column (ODS 100A˚, 5 µm; 4.6 × 250 mm),flow rate (0.9 mL min-1), column temperature (30 °C) and UV-detection wavelength (204 nm). The chromatographic variables: pH (A), % methanol fraction (B), flow rate(C) and column temperature (D) were optimized at 50 µg mL-1caffeine using BBD model. The chromatogram resulted in the asymmetry factor (1.23), theoretical plate 13,786 and retention time (5.79 min). The proposed HPLC method's greenness point was assessed byAnalytical Eco-scale and found to be 78 (as per guidelines, ranked as excellent). The linearity was ranged from2.0 to 70 µg mL-1 with coefficient of correlation (r = 0.999) and detection limit of 0.19 µg mL-1. The proposedmethod was developed successfully and applied for the assay of active caffeine in pharmaceutical preparations and urine samples. The % recovery obtained by both (proposed and reference) methods ranged from 99.98 to 100.05 % followed the compliance (100 ± 2 %) with Canadian Health Protection regulatory guidelines. The performance of the proposed method was compared with published papers and found to be acceptable and superior. The proposed method was quite effective as the reference method, and hence can be used as an alternative method for the assay of active caffeine in pharmaceutical preparations and urine samples.


Assuntos
Cafeína , Metanol , Cafeína/análise , Cromatografia Líquida de Alta Pressão/métodos , Canadá , Preparações Farmacêuticas
8.
PLoS One ; 19(2): e0296526, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324553

RESUMO

The study introduces a methodology that utilizes data-driven approaches to optimize coffee drying operations. This is achieved through the integration of ambient sensor data and chemical analysis. This statement underscores the significance of temperature regulation, humidity levels, and light intensity within the context of coffee production. There exists a positive correlation between elevated temperatures and increased rates of drying, but humidity has a role in determining the duration of the drying process and the preservation of aromatic compounds. The significance of light intensity in dry processing is also crucial, since excessive exposure can compromise both the taste and quality of the product. The findings of chemical investigations demonstrate a correlation between environmental factors and the composition of coffee. Specifically, increased temperatures are associated with higher quantities of caffeine, while the concentration of chlorogenic acid is influenced by humidity levels. The research additionally underscores the variations in sensory characteristics among various processing techniques, underscoring the significance of procedure choice in attaining desirable taste profiles. The integration of weather monitoring, chemical analysis, and sensory assessments is a robust approach to augmenting quality control within the coffee sector, thereby facilitating the provision of great coffee products to discerning consumers.


Assuntos
Café , Compostos Orgânicos Voláteis , Café/química , Cafeína/análise , Dessecação/métodos , Cromatografia Gasosa , Compostos Orgânicos Voláteis/análise
9.
Chemosphere ; 352: 141444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38346513

RESUMO

This study assessed the occurrence of five antibiotics, three hormones, caffeine, and long and short-chain perfluoroalkyl and polyfluoroalkyl substances (PFASs) in surface water and feedstuff samples obtained from aquaculture cages in Três Marias reservoir in Brazil. This is the first work to evaluate the presence of PFAS in surface water used for aquaculture in Brazil. Solid-phase extraction and low temperature partitioning extraction followed by liquid chromatography coupled to mass spectrometry (LC-MS) were performed to process and analyze surface water samples and feedstuff, respectively. The ecotoxicological risk quotient was calculated for target compounds detected in water. Ciprofloxacin and caffeine were detected in all surface water samples. Pharmaceutical drugs ranged from 0.7 ng L-1 (trimethoprim) to 389.2 ng L -1 (ß-estradiol). Estrone (10.24 ng g-1) and ß-estradiol (66.20 ng g-1) were also found in feedstuff. Four PFASs (PFOA, PFDoA, PFTeDA, and PFBS) were detected (9.40-15.2 µg L-1) at levels higher than reported in studies conducted worldwide. Ecotoxicological risk assessment indicated high risks for caffeine and PFOA, PFDoA, and PFTeDA with RQ values from 10 to 103. These findings reveal risks to biodiversity, ecosystem integrity and human health considering possible intake of these contaminants by fish consumption due to potential bioaccumulation of these substances. Hence, it is critical to conduct more studies in this direction in Brazil and other low and middle-low-income countries.


Assuntos
Ácidos Alcanossulfônicos , Ciclídeos , Fluorocarbonos , Poluentes Químicos da Água , Humanos , Animais , Água/análise , Brasil , Monitoramento Ambiental , Antibacterianos/análise , Ácidos Alcanossulfônicos/análise , Cafeína/análise , Ecossistema , Estradiol/análise , Poluentes Químicos da Água/análise , Fluorocarbonos/análise
10.
Prev Med ; 180: 107889, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325607

RESUMO

The consumption of energy drinks poses significant risks to minors' health, and strict regulations are urgently needed to protect them. The high caffeine, high sugar, and high caloric content of energy drinks have drawn concern from health professionals. The consumption of energy drinks has been linked to unhealthy dietary behaviors, obesity, and mental health problems in adolescents. The psychoactive and stimulant effects of energy drinks are particularly worrisome, and the marketing of these drinks on social media platforms is also a cause for alarm. In light of these concerns, we strongly recommend policy measures, such as restrictions on the sale of energy drinks to minors, to prevent their health risks. The evidence clearly suggests that energy drinks pose significant risks to minors' health and well-being, and regulatory standards must be implemented without further delay.


Assuntos
Bebidas Energéticas , Adolescente , Humanos , Bebidas Energéticas/efeitos adversos , Cafeína/análise , Europa (Continente) , Marketing , Comércio
12.
Food Chem ; 441: 138341, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38176147

RESUMO

The key components dominating the quality of green tea and black tea are still unclear. Here, we respectively produced green and black teas in March and June, and investigated the correlations between sensory quality and chemical compositions of dry teas by multivariate statistics, bioinformatics and artificial intelligence algorithm. The key chemical indices were screened out to establish tea sensory quality-prediction models based on the result of OPLS-DA and random forest, namely 4 flavonol glycosides of green tea and 8 indices of black tea (4 pigments, epigallocatechin, kaempferol-3-O-rhamnosyl-glucoside, ratios of caffeine/total catechins and epi/non-epi catechins). Compared with OPLS-DA and random forest, the support vector machine model had good sensory quality-prediction performance for both green tea and black tea (F1-score > 0.92), even based on the indices of fresh tea leaves. Our study explores the potential of artificial intelligence algorithm in classification and prediction of tea products with different sensory quality.


Assuntos
Camellia sinensis , Catequina , Chá/química , Inteligência Artificial , Cafeína/análise , Camellia sinensis/química , Catequina/análise , Algoritmos
13.
Food Res Int ; 176: 113791, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163705

RESUMO

Coffee is one of the most consumed beverages worldwide. Espírito Santo is the largest Brazilian producer of conilon coffee, and invested in the creation of new cultivars, such as "Conquista ES8152", launched in 2019. Therefore, the present study aimed to evaluate the effects of maturation and roasting on the chemical and sensorial composition of the new conilon coffee cultivar "Conquista ES8152". The coffee was harvested containing 3 different percentages of ripe fruits: 60%, 80%, and 100%, and roasted at 3 different degrees of roasting: light, medium, and dark, to evaluate the moisture and ash content, yield of soluble extract, volatile compound profile, chlorogenic acid and caffeine content, and sensory profile. "Conquista ES8152" coffee has a moisture content between 1.38 and 2.62%; ash between 4.34 and 4.72%; and yield between 30.7 and 35.8%. Sensory scores ranged between 75 and 80 and the majority of volatile compounds belong to the pyrazine, phenol, furan, and pyrrole groups. The content of total chlorogenic acids was drastically reduced by roasting, with values between 2.40 and 9.33%, with 3-caffeoylquinic acid being the majority. Caffeine was not influenced by either maturation or roasting, with values between 2.16 and 2.41%. The volatile compounds furfural, 5-methylfurfural, and 2-ethyl-5-methylpyrazine were positively correlated with the evaluated sensory attributes and 5-methylfurfural was the only one significantly correlated with all attributes. Ethylpyrazine, furfuryl acetate, 1-furfurylpyrrole, 4-ethyl-2-methoxyphenol, and difurfuryl ether were negatively correlated. The stripping did not affect the quality and composition of this new cultivar, however, the roasting caused changes in both the chemical and sensorial profiles, appropriately indicated by the principal component analysis.


Assuntos
Coffea , Café , Café/química , Coffea/química , Quimiometria , Cafeína/análise , Ácido Clorogênico/análise
14.
Food Res Int ; 176: 113814, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163718

RESUMO

FTIR spectroscopy and multivariate analysis were used in the chemical study of the terroirs of Coffea canephora. Conilon coffees from Espírito Santo and Amazon robusta from Matas of Rondônia, were separated by PCA, with lipids and caffeine being the markers responsible for the separation. Coffees from Bahia, Minas Gerais, and São Paulo did not exhibit separation, indicating that the botanical variety had a greater effect on the terroir than geographic origin. Thus, the genetic factor was investigated considering the conilon and robusta botanical varieties. This last group was composed of hybrid robusta and apoatã. The DD-SIMCA favored the identification of the genetic predominance of the samples. PLS-DA had a high classification performance regarding the conilon, hybrid robusta, and apoatã genetic nature. Lipids, caffeine, chlorogenic acids, quinic acid, trigonelline, proteins, amino acids, and carbohydrates were identified as chemical markers that discriminated the genetic groups.


Assuntos
Coffea , Coffea/genética , Coffea/química , Cafeína/análise , Brasil , Café/química , Lipídeos
15.
Anal Methods ; 16(8): 1158-1174, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38189175

RESUMO

The growing interest in health and well-being has spurred the evolution of functional foods, which provide enhanced health benefits beyond basic nutrition. Guaraná seeds (Paullinia cupana) have been widely studied and used as a functional food due to their richness in caffeine, phenolic compounds, amino acids, and other nutrients. This has established guaraná as a significant food supplement, with Brazil being the largest producer of the world. This study aims to propose a set of analytical methods to chemically evaluate fifty-six different guaraná clones, from the Guaraná Germplasm Active Bank, to accommodate the diverse requirements of the food industry. Metabolomic approaches were employed, in which a non-target metabolomic analysis via UPLC-QTOF-MSE led to the annotation of nineteen specialized metabolites. Furthermore, targeted metabolomics was also used, leading to the identification and quantification of metabolites by NMR. The extensive data generated were subjected to multivariate analysis, elucidating the similarities and differences between the evaluated guaraná seeds, particularly concerning the varying concentration levels of the metabolites. The metabolomics approach based on the combination of UPLC-QTOF-MSE, NMR and chemometric tools provided sensitivity, precision and accuracy to establish the chemical profiles of guaraná seeds. In conclusion, evaluating and determining the metabolic specificities of different guarana clones allow for their application in the development of products with different levels of specific metabolites, such as caffeine. This caters to various purposes within the food industry. Moreover, the recognized pharmacological properties of the annotated specialized metabolites affirm the use of guarana clones as an excellent nutritional source.


Assuntos
Cafeína , Paullinia , Cafeína/análise , Cafeína/metabolismo , Paullinia/química , Paullinia/metabolismo , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/química , Sementes/metabolismo
16.
J Food Sci ; 89(1): 81-95, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37983847

RESUMO

Shaking and tumbling are extremely important for the formation of the special flavor of Wuyi rock tea. In this study, we analyzed the effects of different shaking and tumbling degrees on the quality index content of tea leaves and determined changes in gene expression in tea leaves using RNA sequencing technology. On this basis, the correlation between gene expression intensities in tea leaves and tea quality index content was analyzed. The results showed that heavy shaking and tumbling (MW3) increased gene expression of metabolic pathways, biosynthesis of secondary metabolites, starch and sucrose metabolism, biosynthesis of amino acids, glycine, serine, and threonine metabolism, alpha-linolenic acid metabolism pathways and decreased gene expression of flavonoid biosynthesis, carbon fixation in photosynthetic organisms, phenylpropanoid biosynthesis, and plant hormone signal transduction pathways in tea leaves, which in turn increased the content of caffeine, soluble sugar, amino acid and decreased the content of flavone, tea polyphenol, catechin component in tea leaves; the opposite was true for light shaking and tumbling. Second, this study found that MW3 was more beneficial in improving the mellowness, sweetness, and fresh and brisk taste of tea leaves and reducing the bitterness of tea leaves. This study provides some references to guide the processing of Wuyi rock tea with different flavors. PRACTICAL APPLICATION: Heavy shaking and tumbling was more beneficial in improving the mellowness, sweetness, and fresh and brisk taste of tea leaves and reducing the bitterness of tea leaves. Therefore, the degree of shaking and tumbling in Wuyi production can be appropriately improved to produce high-quality tea and improve the economic benefits of tea.


Assuntos
Camellia sinensis , Chá , Chá/química , Camellia sinensis/química , Cafeína/análise , Perfilação da Expressão Gênica , Polifenóis/análise , Folhas de Planta/química
17.
J Gastroenterol Hepatol ; 39(3): 512-518, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38073066

RESUMO

BACKGROUND AND AIM: Although diet is one of the potential environmental factors affecting ulcerative colitis (UC), evidence is not sufficient to draw definitive conclusions. This Japanese case-control study examined the association between the consumption of coffee, other caffeine-containing beverages and food, and total caffeine and the risk of UC. METHODS: The study involved 384 UC cases and 665 control subjects. Intake of coffee, decaffeinated coffee, black tea, green tea, oolong tea, carbonated soft drinks, and chocolate snacks was measured with a semiquantitative food-frequency questionnaire. Adjustments were made for sex, age, pack-years of smoking, alcohol consumption, history of appendicitis, family history of UC, education level, body mass index, and intake of vitamin C, retinol, and total energy. RESULTS: Higher consumption of coffee and carbonated soft drinks was associated with a reduced risk of UC with a significant dose-response relationship (P for trend for coffee and carbonated soft drinks were <0.0001 and 0.01, respectively), whereas higher consumption of chocolate snacks was significantly associated with an increased risk of UC. No association was observed between consumption of decaffeinated coffee, black tea, green tea, or oolong tea and the risk of UC. Total caffeine intake was inversely associated with the risk of UC; the adjusted odds ratio between extreme quartiles was 0.44 (95% confidence interval: 0.29-0.67; P for trend <0.0001). CONCLUSIONS: We confirmed that intake of coffee and caffeine is also associated with a reduced risk of UC in Japan where people consume relatively low quantities of coffee compared with Western countries.


Assuntos
Café , Colite Ulcerativa , Humanos , Cafeína/efeitos adversos , Cafeína/análise , Japão/epidemiologia , Estudos de Casos e Controles , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/etiologia , Colite Ulcerativa/prevenção & controle , Fatores de Risco , Chá/efeitos adversos
18.
Food Chem ; 439: 138127, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064834

RESUMO

Our study investigated the impact of nitrogen fertilization at 0, 150, 300, and 450 kg/ha on the non-volatile and volatile substances, as well as gene expression in fresh leaves from Lingtou tea plants. We found that applying nitrogen at 450 kg/ha notably increased total polyphenols (TPs) and free amino acids (AAs) while decreasing the TP to AA ratio (TP/AA) and total catechins (TC) contents. Chlorophyll, caffeine (CAF) and theanine accumulated to a greater extent with nitrogen application rates of 150, 300, and 450 kg/ha, respectively, six substances - TP, CAF, TC, theanine, epigallocatechin (EGC), and AA - as key contributors to the taste quality of LTDC. Additionally, five substances with variable importance in projections (VIP) ≥ 1 and odor activation values (OAV) ≥ 1, notably linalool and cis-linalool oxide (furanoid), significantly contributed to the tea's overall aroma. Furthermore, applying 300 kg/ha nitrogen upregulated the dihydroflavonol reductase (DFR)gene, likely causing catechin decrease.


Assuntos
Camellia sinensis , Catequina , Chá/química , Camellia sinensis/química , Nitrogênio/análise , Cafeína/análise , Catequina/química , Folhas de Planta/genética , Folhas de Planta/química , Fertilização
19.
Sci Total Environ ; 912: 168680, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37996029

RESUMO

A reconnaissance survey was undertaken to evaluate the occurrence and risks of 27 pharmaceuticals and metabolites in the St. Lawrence watershed. Surface water samples were collected over a five-year period (2017-2021) along a 700-km reach of the St. Lawrence River as well as 55 tributary rivers (overall N = 406 samples). Additionally, depth water samples and sediments were collected near a major wastewater effluent. Caffeine, diclofenac, and venlafaxine were the most recurrent substances (detection rates >80 %), and extremely high levels were found near a municipal effluent (e.g., ibuprofen (860 ng/L), hydroxyibuprofen (1800 ng/L) and caffeine (7200 ng/L)). Geographical mapping and statistical analyses indicated that the St. Lawrence River water mass after the Montreal City effluent was significantly more contaminated than the other water masses, and that contamination could extend up to 70 km further downstream. This phenomenon was repeatedly observed over the five years of sampling, confirming that this is not a random trend. A slight increase in contamination was also observed near Quebec City, but concentrations rapidly declined in the estuarine transition zone. Tributaries with the highest pharmaceutical levels (ΣPharmas ∼400-900 ng/L) included the Mascouche, Saint-Régis, and Bertrand rivers, all located in the densely populated Greater Montreal area. When flowrate was factored in, the top five tributaries in terms of mass load (ΣPharmas ∼200-2000 kg/year) were the Des Prairies, Saint-François, Richelieu, Ottawa, and Yamaska rivers. All samples met the Canadian Water Quality Guideline for carbamazepine. Despite the large dilution effect of the St. Lawrence River, a risk quotient approach based on freshwater PNEC values suggested that four compounds (caffeine, carbamazepine, diclofenac, and ibuprofen) could present intermediate to high risks for aquatic organisms in terms of chronic exposure.


Assuntos
Poluentes Químicos da Água , Canadá , Poluentes Químicos da Água/análise , Cafeína/análise , Diclofenaco , Ibuprofeno , Carbamazepina/análise , Preparações Farmacêuticas , Monitoramento Ambiental
20.
Food Chem ; 441: 138262, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38160520

RESUMO

This work outlines the simultaneous estimation of the total phenolic and alkaloid contents in the tea samples by using catechin (C) and caffeine (CAF) oxidation signals at a non-modified boron-doped diamond (BDD) electrode. Two irreversible oxidation peaks, about + 1.03 (for C) and + 1.45 V (for CAF) vs Ag/AgCl in acetate buffer solution at pH 4.7, were seen in the cyclic voltammetric profile of the binary mixtures of C and CAF. In optimal conditions and utilizing the square-wave mode, the BDD electrode allows for simultaneous quantification of C and CAF within the concentration ranges of 5.0-100.0 µg mL-1 (1.72 × 10-5 - 3.45 × 10-3 mol/L) and 1.0-50.0 µg mL-1 (5.15 × 10-6 - 2.57 × 10-4 mol/L) respectively. The corresponding detection limits are 1.22 µg mL-1 (4.21 × 10-6 mol/L) for C and 0.11 µg mL-1 (5.66 × 10-7 mol/L) for CAF. Other phenolic compounds (like tannic acid, gallic acid, epicatechin, and epigallocatechin gallate) and other alkaloids (theophylline and theobromine) present in tea samples were examined for selectivity assessment. Ultimately, the applicability of the proposed approach was demonstrated by estimating the total phenolic and alkaloid contents in the black and green tea samples, expressed as C and CAF equivalents. The results obtained were contrasted against those acquired using UV-Vis spectrometry.


Assuntos
Alcaloides , Catequina , Polifenóis , Cafeína/análise , Catequina/análise , Alcaloides/análise , Chá/química , Fenóis/análise , Eletrodos
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